Detergent composition



Patented Jan. 17, 1950 UNITED STATE S PATENT OFFICE DETERGENTCOMPOSITION Walter C. Preston, Cincinnati, Ohio, assignor to The Procter& Gamble Company, Cincinnati, Ohio, a corporation of Ohio No Drawing.Application May 24, 1947, Serial No. 750,369.

It is well known that the use of ordinary toilet or household soap inhard water results in the formation and precipitation of insoluble fattyacid salts, more commonly referred to as lime soaps. It is also knownthat such precipitated lime soaps have a tendency to coagulate and forma sticky curd. This curd is commonly observed in the wash stand and bathtub and also in the laundry rinse tub where it rises to the surface-ofthe water as a scum, adheres to the walls of the tub as a ring, andsticks to the clothes during the rinsing operation, thereby giving tothe clothes an unsightly dingy appearance, producing spots uponsubsequent ironing, and often causing the development of a rancid odor.When soap is used for shampooing the hair, rinsing with hard waterresults in deposition of the lime soaps on the hair. In applications asdivergent as the dyeing of textile fabrics and the plating of metals,the formation of lime soaps has undesirable efiects.

In fact, if soap is used in hard water, insoluble lime soap curd formsduring the rinsing process or whenever the soap dilution becomessufliciently great to destroy the foaming and dispersing power of thesoap.

The coagulation of the lime soaps to form soap curd is dependent notonly On the degree of dilution of the soap-in the hard water, but alsoon the age of the solution and on the degree of violence of agitation towhich it is subjected, increasing age and increasing agitation bothbeing important factors in promoting coagulation.

The primary object of the present invention is to provide a soapcomposition which forms little or no lime soap curd when used with hardwater.

Another object is to provide a detergent composition which will not forma sticky lime soap curd which will cling to clothes or form theunsightly, diflicultly removable soap ring in the washstand or bathtub.

A further object is to increase the resistance of soap-containingdetergent compositions to precipitation of lime soap and the coagulationthereof to form curd when such compositions are used in hard water underconditions involving prolonged standing or agitation.

It is known that synthetic detergents such as mixed or used with soap inhard water are capable of reducing the formation of lime soap curd.Several such mixtures have been proposed. Some have been commerciallyproduced and designated as hard water soaps, allegedly free of curdforming characteristics when used in hard water. However, according tomy investigations and experience, products prepared in accordance withprior art practices, even those which contain more synthetic detergentthan soap, frequently form objectionable curd in hard water under normalconditions of use. As' the proportion of synthetic detergent increases,the trouble with such hard-water curd may decrease in seriousness, butat the same time the cost of the product increases and some of thedesirable physical properties found in soap are adversely affected.

As more fully hereinafter described, I have discovered that esters ofallyl alcohol and soapforming carboxylic acids (although possessing nopower to inhibit curd formation when used with soap alone) have a markedpower to inhibit lime soap precipitation and curd formation in the caseof curd-forming detergent compositions comprising essentially a mixtureof soap and synthetic detergent in proportions more fully hereinafterdescribed. This power exists even when the compositions are used underconditions wherein the solution is subjected to prolonged standing or tomild or vigorous agitation.

I am aware that prior workers in the art. have suggested the combinationof soap with synthetic detergents (Patents 1,906,484, 2,026,816 and2,088,308). None of these patents, however, suggests the use of allylesters of higher carboxylic acids for inhibiting the curd formation whencompositions comprising soap and synthetic detergent are employed inhard water.

Allyl esters which come within the scope of H atoms' in the molecule. ofespecial interest are various organic sulfonates and sulfates, when Nthe allyl esters of saturated fatty acids having from 10 to 14 carbonatoms.

Some specific esters which may be used in the practice of theinventionare: allyl caprate, allyl laurate, allyl myristate, allylpalmitate, allyl stearate, and allyl oleate.

Instead of employing esters of single fatty acids as above indicated,corresponding esters of mixtures of fatty acids, especially thosemixtures ob parting from the spirit of the invention. For ex ample,those esters of a mixture of fatty acids derived from oils of thecoconut oil group (a group of tropical nuts oils characterized by theirhigh content of lauric and myristic acids) such as coconut oil, palmkernel oil, and babassu oil are of particular value, but those esters ofmixtures of fatty acids derived from other oils and fats such as palmoil, tallow, cottonseed oil, sunflower seed oil, fish oils such asmenhaden oil and the like, as well as hydrogenated and partiallyhydrogenated fats and oils ingeneral, may also be employed. In addition,allyl esters of higher aliphatic carboxylic acid mixtures having fromabout to about carbon atoms and derived by oxidation of paraflinhydrocarbons of petroleum or obtained by hydrogenation of carbonmonoxide (commonly known as the Fischer- Tropsch process) or indirectlyby oxidation of the saturated or unsaturated hydrocarbons oxygenatedhydrocarbons resulting from this this process are, suitable in thepractice of my invention.

The kind of soap which is used in preparing my improved detergentcompositions is not limitation of the invention. Any of thewater-soluble soaps formulated for industrial, household and toilet usemay be employed. Thus the character of the soap constituent may varywidely in its composition depending on whether the final ternarycomposition is to be in powdered, spray dried, flake, bar, paste,thread, liquid or other form, and it is to be understood that thespecific soaps referred to in the example given below and prepared fromtallow and coconut oils and are not to be construed as limiting innature. We.- ter-soluble soaps such as the sodium soaps and othersuitable alkali metal or ammonium soaps derived from other fats and oilssuch as cottonseed oil, soybean oil, corn oil, olive oil, palm oil,peanut oil, palm kernel oil, lard, greases, fish oils and the like aswell as their hydrogenated derivatives, and mixtures thereof, properlyblended to yield the desired soap quality, may be used in compoundingthe ternary mixtures herein contemplated.

The synthetic detergent constituent of the present detergentcompositions may be broadly designated as a detergent of the classconsisting of water-soluble salts of organic sulfonic acids andwater-soluble salts of aliphatic sulfuric acid esters, that is,water-soluble salts of organic sul-' furic reaction products having inthe molecular structure a radical selected from the group consisting ofsulfonic acid and sulfuric acid ester radicals. As indicated above inthe designation of the soaps which may be used in compounding thecompositions of my invention, the choice of synthetic detergent willdepend inter alia on the physical characteristics of the final product,that is, whether the composition is to be in flake, bar, paste, or otherform. Obviously if a. detergent composition in bar form is; desired, itwill be impractical to combine ingredients which are too soft to retaintheir shaped form in use.

Synthetic detergents of special interest and particular value are thewater-soluble salts of higher alkyl sulfuric acids containing from 8 to18 carbon atoms in the alkyl radical. More specifically, the alkalimetal salts of sulfuric acid esters of normal primary aliphatic alcoholshaving Hi to H3 carbon atoms, particularly those whose principal activeingredients is a watersoluble salt of lauryl sulfuric acid or oleylsulfuric acid, have proved of value in compounding products of thepresent invention. Thus the sodium salt of alkyl sulfuric acids obtainedfrom the mixed higher alcohols derived by the reduction of coconut oil,palm kernel oil, babassu oil, or other oils of the coconut oil group orthe sodium alkyl sulfate derived from sperm oil alcohols may beemployed. In addit on, water-soluble alkyl sulfates having pronounceddetergent power and derived from high molecular branched chain primaryalcohols or from high molecular secondary alcohols may be used.

Other aliphatic sulfuric acid esters which may be employed in thepreparation of detergent compositions of the present invention includewatersoluble salts of sulfuric acid esters of polyhydric alcoholsincompletely esterfied with high molecular weight soap-formingcarboxylic acids. Such synthetic detergents include the watersolublesalts sulfuric acid esters of higher molecular weight fatty acidmonoglycerides such as sodium salt of the coconut oil fatty acidmonoester of 1, 2-dihydroxy-propane-3-sulfuric acid ester,triethanolamine salt of monooleoyl diethylene glycol sulfate, sodiummono-myristoyl ethylene glycol sulfate, and sodium mono-lauroyldiglycerol sulfate.

Similarly water-soluble salts of ethers of high molecular weight normalprimary alcohols and lower molecular weight hydroxy alkyl sulfuric acidesters may be employed. Specific examples of such synthetic detergentsare sodium salt of mono fatty-a1cohol-of-coconut-oil ether of glycerolmonosulfuric ether of ethylene glycol monosulfuric acid.

In addition, sulfuric acid ester synthetic detergents such aswater-soluble salts of sulfated higher fatty acid alkanolamides, forexample the sodium salt of sulfated coconut oil fatty acid ethanolamideand of sulfated babassu oil fatty acid glycerol amide, may be employedin the practice of the invention.

The allyl esters hereinabove referred to are active also in inhibitingcurd formation in the case of those detergent compositions which containin combination with soap an organic synthetic detergent having a truesulfonate group. These synthetic detergents include salts of highermolecular weight monofatty acid esters of lower molecular weight hydroxyalkyl sulfonic acids such as the sodium salt of the coconut oil fattyacid monoester of 1, -dihydroxy-propane-3-sulfonic acid, and the oleicacid ester of the sodium salt of isethionic acid. Included also are thehigher molecular weight fatty acid amides of lower molecular weightamino alkyl sulfonic acids (for example, sodium and potassium salts ofoleic acid amide of N-methyl taurine), the watersoluble salts of thehigher molecular weight alcohol esters of sulfocarboxylic acids (forexample, sodium salt of the lauryl alcohol'ester of sulfoacetic acid),lower molecular weight sulfocarboxylic acid amides of alkylolamineesters of higher molecular weight fatty acids (for example, sodium saltof the sulfoacetamide of amino ethyl laurate), higher alkylated arylsulfonic acids (for example, sodium and potassium salts of the sulfonicacid derived from the condensation product of benzene and a chlorinatedkerosene fraction containing predominantly 10 to 14 carbon atoms permolecule such as represented by the formula where R is the alkyl group)and ethers of higher acid and sodium salt of lauryl molecular weighthydroxy alkyl sulfonic acids (for example, monolauryl ether of1,2-dihydroxypropane-3-sodium sulfonate and monolauryl ether of thesodium salt of isethionie acid).

Although the essential ingredients of the compositions of the presentinvention comprise essentially a ternary mixture of an allyl alcoholester of a. higher fatty acid, soap and synthetic detergent, it will beappreciated that the incorporation in the mixture of additionalingredients commonly used with cleansing compositions, such as perfumes,starch, urea, triethanolamine, inorganic salts (sulfates, silicates,carbonates, ortho-, meta-, pyro-,and triphosphates and the like),albuminous substances, glycerin, insecticides and germicides and thelike, is contemplated as part of the instant invention.

The following examples will illustrate the manner in which the inventionmay be practiced, but it is to be understood that such details are givenmerely for exempliflcation purposes and are not to be construed aslimiting the scopeof the appended claims. In all instances theproportions are expressed in parts by weight.

Example 1.A mixture was prepar d consisting of 70 parts of sodium soapfrom tallow and 20% coconut oil and containing about 15% water, 25 partsof the. sodium salt of the coconut oil fatty acid mono-ester of1,2-dihydroxypropane-3-sulfonic acid (commonly known as coconut oilmonoglyceride sulfonate) and 5 parts of allyl laurate. The ratio of soapto synthetic in this mixture was about 2.4:1, and the ratio of syntheticto allyl laurate was 5:1. A 0.04% solution of this mixture in 20 grainwater was shaken vigorously, but no hard-water soap curd was formed. Atthe same time and when tested in the same manner, mixtures containingeither (a) 70 parts of the same soap and 30 parts of the same syntheticdetergent, or (b) '75 parts of the same soap and 25 parts of the samesynthetic detergent gave hard-water soap curd. This showed thatsubstituting 5 parts of allyl laurate for 5 parts of either the soap orthe synthetic detergent in such a mixture of the twopromotes the powerof the synthetic detergent to inhibit curd formation. In admixture withsoap alone, allyl laurate had no curd-inhibiting power.

Example 2.In the manner described in Ex ample 1 and using the samematerials therein used, the following three mixtures were compared, withthe results shown in the table below.

lConcentration, 0.04%; water hardness, 20 grains per gallon] Parts ofsoap 1 70 -70 Parts of synthetic detergent. 30 20 Parts of allyl laurate0 0 Ratio, Soap: Synthetic 2:1 3:1 3.4.1 Ratio, Synthetic: Ally]laurate. 2:1 Result of shaking curd no curd curd 1 This soap containedabout water.

1,- 40 parts of a commercial synthetic detergent containing about 88%sodium salt of the sulfuric acid ester of alcohols derived from coconutoil (the remaining 12% being largely Nazsol). and

10' parts of allyl laurate, to which mixture about 4 parts of'water areadded as needed to give and maintain the proper working consistencyduring milling and subsequent plodding.- The resulting milled ribbonsare then plodded in customary soap-making equipment, and the ploddedproduct is cut and stamped in the form of bars. The

a ratio of soap to synthetic detergent in these bars is about 1.2:1, andthe ratio of synthetic detergent to allyl laurate is about 35:1.

Example '4.Milled bars are made by the procedure of Example 3, using 65parts of the soap therein used, 25 parts of the sodium salt of babessufatty acid mono-ester of 1,2-dihydroxy-propane-3-sulfonic acid, and 10parts of allyl esters of babassu oil fatty acids. These bars lather andcleanse well and do not give objectionable curd in 20 grain water. Theratio of soap to synthetic in these bars is about 2.221, and the ratioof synthetic to allyl ester is about 2L5:1.

Example 5.-Mil1ed bars are made by the procedure of Example 4, using51.8 parts of the soap therein used, 48 parts of the synthetic detergentused therein, and 8 parts of the allyl esters of mixed babassu fattyacids. These bars lather and clean well and do not give objectionablecurd in 20 grain water. The ratio of soap to synthetic in these bars isabout 09:1, and the ratio of synthetic to allyl ester is about 6:1.

Example 6.---Detergent flakes which suds and cleanse satisfactorily anddo not give objectionable curd in 20 grain water are made by milling onsoap-milling rolls a mixture consisting of 74 parts of sodium soap from75% tallow and 25% coconut oil and containing about 3% water, 30.3

- sulfonate, and 24 parts of allyl myristate.

parts of a dried neutralized reaction product of oleum with coconutfatty acid esters of allyl alcohol consisting of about 66% coconutmonoglyceride sulfonate, about 7.3% sodium soap of coconut oil fattyacids, and about 26.7% NazS04, and 6 parts of the coconut fatty acidesters of allyl alcohol, to which mixture a little water is added asrequired .to give plasticity to the resulting milled ribbons. The milledribbons are converted into flake form in known manner. The ratio of soapto synthetic detergent in these flakes is about 3.7:1, and the the ratioof synthetic detergent to allyl ester is about 3.3:1.

Example 7.-Detergent flakes are prepared by the procedure of Example 6,using 51.6 parts of sodium soap from tallow containing about 3% water,70 parts of a commercial alkyl aryl sulfonate detergent containing about40% alkyl benzene sulfonate sodium salt and about nalsoi,

and 22 parts of allyl esters of coconut fatty acids, and adding a littlewater as needed on the rolls.

The resulting flakes suds and cleanse well and do not give objectionablecurd in 20 grain water. The ratio of soap to synthetic detergent inthese flakes'is about 1.8:1, and the ratio of synthetic detergent toallyl ester is about 1.3:1.

Example 8.-Detergent flakes are made by the procedure of Example 6,using 33 parts of sodium soap made from tallow and'containing about 3%water, 44 parts-of the mixed coconut fatty acid mono-esters of1,2-dihydroxy-propane-3-sodium The flakes suds and clean well and do notgive objectionable curd in 20 grain water. The ratio of soap tosynthetic in these flakes is about 0.7:1, and

ing of 50 parts of the soap described in Example 76 the ratio ofsynthetic to allyl ester is about.1.8:l.

sentativeof hard waters in general.

In the above examples, reference has been made to use in water of 20grains of hardness per gal- 1011. It is to be understood, however, that20 grain water is referred to only as being repre- According to myexperience and investigations, my ternary detergent composition iseffective in hard water of any municipal water system or anydomestically used water sourceof which I am aware.

Besides possessing resistance to curd formation in hard water, productsof the present invention dissolve at a desirable rate in the water, sudsprofusely, and cleanse efllciently. Addition of theallyl ester to thesoap-synthetic detergent mixtures, as specified in the application,tends in general to increase the sudsing power of the.composition.However, excessive additions of the ester are to be avoided, as they maydecrease sudsing power, harm the desired physical properties of thedetergent bar, flake or other product, and interfere with handling insome of the common soap manufacturing processes. h

It is especially noteworthy that the bar products I of my invention havea definite advantage over bars consisting in very large measure ofsynthetic detergent in that they do not dissolve too rapidly, do notbecome soft, are more soap-like in appearance and feel, and behave morelike soap in processing operations, and produce a lather which isgenerally similar in structure and feel to that of soap, being unlikethat produced by the synthetic alone.

The amount of allyl ester that can advantageously be used is to a degreedependent upon the nature and amount of synthetic detergent present inthe composition. The most useful products result when the amount ofallyl ester exceeds one sixth of, but is not greater than, the amount ofsynthetic detergent present and constitutes at least 2 per cent of thecombined weight of soap, synthetic detergent and allyl ester.

Most of the above examples cover compositions in which the ratios ofessential ingredients come within the preferred ranges, that is, a ratioof soapzsynthetic from about %:1 to about 4:1, and a ratio ofsyntheticzallyl ester from about 1%:1 to about 6:1. The advantages of mydiscovery, however, areto be realized even in compositions fallingoutside the preferred ranges of proportions, and accordinglycompositions coming within the ratios of soapzsynthetic of about %:1 toabout 8:1 and of syntheticzallyl ester of about 1:1 to about 10:1 arecontemplated as part of the broad invention, the allyl esterconstituting at least 2 per cent of the combined weights of soap,synthetic and ester. Optimum results in the case of each composition maybe realized by adjustment of the ratios used depending on the types ofsoap, synthetic detergent and ester employed.

'As indicated above, the physical form of the compositions is not alimitation of the invention and may be varied in well known manner. Insome instances, however, it may be necessary to adjust temperatureconditions or moisture content of the mixture to give a product of thedesired consistency for handling in the various processing operationsrequired in the development of the desired physical form. Suchadjustments of course are well within the scope of those skilled in theart. v V

The manner of mixing the ingredients is not a limitation of theinvention. Any suitable mixing device such as a series of milling rollsordiufacturing the said sulfonated monoglyceride.

For example, I may prepare the sulfonated monoglyceride by treating anallyl ester with chlorosulfonic acid, and, by suitably controlling theconditions of sulfonation, i. e. time, temperature or sulfonating agentconcentration, a reaction product containing the desired proportion oiunsulfonated allyl ester may be obtained.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

l. A detergent composition characterized by reduced tendency to formlime soap curd when used in hard water, comprising essentially a ternarymixture of a water-soluble soap, t soluble salt of an organic sulfuricreaction product having pronounced detergent properties and having inits molecular structure a radical selected from the group consisting ofsulfonic acid and sulfuric acid ester radicals, and an ester of allylalcohol and a soap-forming carboxylic acid, the ratio of soap :sulfuricreaction product salt being from /2 :1 to 8:1 and the ratio of sulfuricreaction product saltzester being from 1:1 to 10:1, and the amount ofester constituting at least 2 per cent of the combined weights of soap,sulfuric reaction product salt, and ester.

2. A detergent composition characterized by reducedtendency to form limesoap curd when used in hard water, comprising essentially a ternarymixture of a water-soluble soap, a watersoluble salt of an organicsulfuric reaction product having pronounced detergent properties andhaving in its molecular structure a radical selected from the groupconsisting of sulfonic acid and sulfuric acid ester radicals, and anester of allyl alcohol and a soap-forming carboxylic acid, the ratio ofsoapzsulfuric reaction product salt being from %:1 to 4:1 and the ratioof sulfuric reaction product salt:ester being from l /2:1 to 6: 1.

3. The composition of claim 1 in which the ester of allyl alcohol isderived from a mixture of fatty acids obtained from a member of thegroup consisting of animal and vegetable oils and fats.

4. The composition of claim 1 in which the ester of allyl alcohol isderived predominantly from saturated fatty acids having 10 to 14 carbonatoms.

5. The composition of claim 1 in which the ester of allyl'alcohol isderived from a mixture of higher molecular fatty acids of coconut oilconsisting predominantly of fatty acids having 10 to 14 carbon atoms.

6. The composition of claim 1 in which the organic sulfuric reactionproduct salt is a watersoluble salt of an alkyl sulfuric acid havingfrom 10 to 25 carbon atoms in the alkyl radical.

7. The composition of claim 1 in which the sulfuric reaction productsaltis a water-soluble salt of alkyl sulfuric acids of higher alcoholsderived from tropical nut oils characterized by their high content oflauric and myristic acids.

8. The composition of claim 1 in which the sulfuric reaction productsalt consists essentially of a water-soluble salt of dodecyl sulfuricacid and in which the ester is the allyl alcohol ester of fatty acids oftropical nut oils characterized by their high content of lauric andmyristic acids.

9. The composition of claim 1 in which the sulfuric reaction productsalt is a water-soluble salt of an alkyl sulfuric acid having 10 to 14carbon atoms inthe alkyl radical and in which the ester is the allylalcohol ester of fatty acids having 10 to 14 carbon atoms.

10. The composition of claim 1 in which the sulfuric reaction productsalt consists essentially of a water-soluble salt of the coconut oilfatty acid mono-ester of 1,2-dihydroxy-propane-3- sulfonic acid.

11. The composition of claim 1 in which the sulfuric reaction productsalt consists essentially of a water-soluble salt of the coconut oilfatty acid mono-ester of 1,2-dihydroxy-propane-3- sulfonic acid and inwhich the ester is the allyl alcohol ester of fatty acids of tropicalnut oils characterized by their high content of lauric and myristicacids.

12. The composition of claim 1 in which the sulfuric reaction productsalt is a water-soluble salt of a higher alkylated aryl sulfonic acid.

13. The composition of claim 1 in which the sulfuric reaction productsalt is essentially a water-soluble salt of an alkylated benzenesulfonlc acid of the composition WALTER c. PRESTON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS 25 Number Name Date 1,906,484 Nuesslein May 2.1933 2,026,816 Bertsch Jan. 7, 1938 2,175,285

Duncan Oct. 10, 1939

1. A DETERGENT COMPOSITION CHARACTERIZED BY REDUCED TENDENCY TO FORMLIME SOAP CURD WHEN USED IN HARD WATER, COMPRISING ESSENTIALLY A TERNARYMIXTURE OF A WATER-SOLUBLE SOAP, A WATERSOLUBLE SALT OF AN ORGANICSULFURIC REACTION PRODUCT HAVING PRONOUNCED DETERGENT PROPERTIES ANDHAVING IN ITS MOLECULAR STRUCTURE A RADICAL SELECTED FROM THE GROUPCONSISTING OF SULFONIC ACID AND SULFURIC ACID ESTER RADICALS, AND ANESTER OF ALLYL ALCOHOL AND A SOAP-FORMING CARBOXYLIC ACID, THE RATIO OFSOAP: SULFURIC REACTION PRODUCT SALT BEING FROM 1/2:1 TO 8:1 AND THERATIO OF SULFURIC REACTION PRODUCT SALT:ESTER BEING FROM 1:1 TO 10:1,AND THE AMOUNT OF ESTER CONSTITUTING AT LEAST 2 PER CENT OF THE COMBINEDWEIGHTS OF SOAP, SULFURIC REACTION PRODUCT SALT, AND ESTER.